Arrangements of this kind are used to guide light from a light source to a desired location with as little loss as possible and there to couple it out of the light guide in accordance with the application, particularly through a window. Depending on the intended use, the widest variety of light sources are combined with such reflector arrangements. Light-emitting or laser diodes, inter alia, can be employed as light sources.
Reflector arrangements find application as general illuminants or as efficient background lighting for liquid crystal displays (LCDs). In such cases, the light is usually guided from the light source to a window, from which it is extracted as uniformly as possible. The light guide often has a roughened surface at the site of the exit window, to homogenize the exiting light. The light guide is usually made from transparent materials, such as for example polymethylmethacrylate (PMMA) or epoxy resin. To minimize losses, the reflector surrounds the light guide in subregions. To be able to surround the light guide, the reflector is formed of plural elements that must be assembled around the light guide during the assembly process.
U.S. Pat. No. 6,259,082 B1 discloses an arrangement composed of a reflector and a light guide in which the reflector is constructed of plural elements that surround the light guide. A variety of equipment and tools is needed to fabricate the individual elements. These parts must then be fitted together during the assembly of such an arrangement. Each of the elements is therefore associated with logistical expenditure. More elements generally make for an increased number of work steps, which can additionally create sources of error in the production process. Large numbers of elements are also, on the whole, associated with higher costs.
The object of the invention is to disclose a reflector arrangement of the initially cited kind, which permits an improvement in a cost-effective manner.
The invention achieves this object by means of the features of claim 1. Configurations of the invention are characterized in the dependent claims.
In the present invention, at least one reflector shaped body is fixedly connected to at least one other shaped body of the reflector via a bendable connector, a so-called film hinge. This reduces the expenditure associated with assembly. Assembly expenditure is limited to the following steps: placing the light guide in the reflector; folding the reflector together; securing the movable parts.
An advantageous embodiment of the invention results if the reflector is implemented in one piece with at least one film hinge, disposed between shaped bodies of the reflector and thereto-assigned fastening means. This advantageously reduces the number of individual parts needed overall. The logistical expenditure involved in shipping the parts and keeping them in stock and the assembly expenditure are reduced, since fewer individual parts are needed to make a reflector arrangement.
A further advantageous embodiment of the invention results if the reflector, together with the film hinge(s), is produced in one piece by injection molding or another molding process. Only one mold with one cavity is therefore needed. In addition, limitation to a single injection point on the mold is thereby feasible. This has economic advantages with regard to production.
In a further advantageous embodiment of the invention, a film hinge is implemented as at least segmentally continuous along the extension of the axis of the hinge. The axis of the hinge is the axis about which shaped bodies of a reflector rotate or fold. It usually lies on a common edge of different shaped bodies.
A further advantageous embodiment of the invention results if a film hinge is implemented not as continuous, but as locally interrupted.
In a further advantageous embodiment of the invention, the reflector arrangement contains an angled light guide.
In a further advantageous embodiment of the invention, the assembled reflector surrounds the light guide.
A further advantageous embodiment of the invention provides that shaped bodies of the reflector that are connected by a film hinge can be secured to one another by means of fasteners.
A further advantageous embodiment of the invention provides that shaped bodies of the reflector that are connected by a film hinge can be secured to the light guide by means of fasteners.
A further advantageous embodiment of the invention provides that shaped bodies of the reflector that are connected by a film hinge can be secured both to one another and to the light guide by means of fasteners.
In a further advantageous embodiment of the invention, a snap mechanism is provided as fastening means for the reflector arrangement. Assembly thus is reduced to inserting the light guide, folding the molded parts together and engaging the snap. The error rate in assembly is also reduced in this way.
In a further advantageous embodiment of the invention, a latch is provided as fastening means for the reflector arrangement. Assembly thus is reduced to inserting the light guide, folding the molded parts together and engaging the latch. The error rate in assembly is also reduced in this way. Latching, in contrast to snapping, permits fastening in a plurality of discrete positions.
In a further advantageous embodiment of the invention, contact surfaces for gluing are provided as fastening means for the reflector arrangement. Assembly thus is reduced to inserting the light guide, folding the molded parts together and gluing the contact surfaces. The error rate in assembly is also reduced in this way.
In a further advantageous embodiment of the invention, contact surfaces for welding are provided as fastening means for the reflector arrangement. Assembly thus is reduced to inserting the light guide, folding the molded parts together and welding the contact surfaces. The error rate in assembly is also reduced in this way.
In a further advantageous embodiment of the invention, contact surfaces for swaging are provided as fastening means for the reflector arrangement. Assembly thus is reduced to inserting the light guide, folding the molded parts together and swaging the contact surfaces. The error rate in assembly is also reduced in this way.
A further advantageous embodiment of the invention provides that the reflector performs a holding function for the light guide. A holding function of the reflector with respect to the light guide can be achieved merely by fitting the reflector exactly to the light guide and having it partially surround the latter. Direct holding modalities are also possible, however. Guide rails, latch lugs or snap lugs may be cited as examples.
In embodiments where a fastener is disposed between the reflector and the light guide, or the reflector at least partially surrounds the light guide in subregions, the reflector can also additionally perform a securing function for the light guide.
A further advantageous embodiment of the invention provides that the reflector comprises one or more light exit windows.
A further advantageous embodiment of the invention provides that the reflector comprises one or more light entrance windows.
The invention will be described below with reference to exemplary embodiments which are illustrated in the figures of the drawing. Elements of the same kind have been provided with the same respective reference numerals.